Composite resin particle with specific shape factor

Abstract

The invention is a composite resin particle useful as an additive for paints or coatings, powder coatings, cosmetic additives, slush molding resins, spacer for electronic part assembly, standard particles for electric measurement devices, toner, hot melt adhesive as well as other molding materials. Said composite resin particle comprises a resin microparticle (A) depositing on the surface of a resin particle (B) wherein the shape factor (SF-1) of said composite resin particle is 115 to 800. It is also a composite resin particle comprising a resin microparticle (A) depositing on the surface of a resin particle (B) wherein the acid vale of a resin (b) constituting the resin particle (B) is 5 to 100.

1. A composite resin particle comprising a resin microparticle (A) depositing on the surface of a resin particle (B) wherein the shape factor (SF-1) of said composite resin particle is 145 to 800. 
     
     
       2. The composite resin particle of  claim 1 , wherein the acid value of a resin (b) constituting the resin particle (B) is 7 to 100. 
     
     
       3. The composite resin particle according to  claim 2  wherein the resin microparticle (A) has a volume average particle diameter (DA) of 0.0005 to 30 μm and the resin particle (B) has a volume average particle diameter (DB) of 0.1 to 300 μm. 
     
     
       4. The composite resin particle according to  claim 2  wherein the resin microparticle (A) and/or the resin particle (B) is at least one resin selected from the group consisting of polyurethane, epoxy resin, vinyl resin and polyester. 
     
     
       5. The composite resin particle according to  claim 2  wherein the resin particle comprises a reactive group-containing prepolymer (α) and a curing agent (β). 
     
     
       6. The composite resin particle according to  claim 2  obtained in such a manner that the resin (b) constituting the resin particle (B), a precursor (b0) of said resin (b) and/or a solution thereof are dispersed in an aqueous dispersion containing the resin microparticle (A) and if the precursor (b0) or a solution thereof is employed the precursor (b0) is reacted, to form the resin particle (B) comprising said resin (b) in the aqueous dispersion of the resin microparticle (A) whereby forming the resin particle as the resin particle (B) on the surface of which the resin microparticle (A) has been deposited and then the aqueous solvent is removed. 
     
     
       7. The composite resin particle according to  claim 1  wherein the resin microparticle (A) has a volume average particle diameter (DA) of 0.0005 to 30 μm and the resin particle (B) has a volume average particle diameter (DB) of 0.1 to 300 μm. 
     
     
       8. The composite resin particle according to  claim 1  wherein the ratio (DA/DB) of the volume average particle diameter (DA) of the resin microparticle (A) to the volume average particle diameter (DB) of the resin particle (B) is 0.0001 to 0.5. 
     
     
       9. The composite resin particle according to  claim 1  wherein the amount of the resin microparticle (A) based on the total weight of the resin microparticle (A) and the resin particle (B) is 0.01 to 60% by weight. 
     
     
       10. The composite resin particle according to  claim 1  wherein the ratio (TA/TC) of the projected area (TA) of the resin microparticle (A) to the projected area (TC) of the composite resin particle is 0.001 to 1. 
     
     
       11. The composite resin particle according to  claim 1  wherein the variation coefficient of the volume average particle diameter (DC) of the composite resin particle is 0.1 to 50%. 
     
     
       12. The composite resin particle according to  claim 1  wherein the ratio (DC/DNC) of the volume average particle diameter (DC) of the composite resin particle to the number average particle diameter (DNC) of the composite resin is 1.0 to 2.5. 
     
     
       13. The composite resin particle according to  claim 1  wherein the resin microparticle (A) and/or the resin particle (B) is at least one resin selected from the group consisting of polyurethane, epoxy resin, vinyl resin and polyester. 
     
     
       14. The composite resin particle according to  claim 1  wherein the resin particle (B) contains a colorant treated with an aluminum coupling agent. 
     
     
       15. The composite resin particle according to  claim 1  wherein the Tg of the resin microparticle (A) is 0 to 300° C. 
     
     
       16. The composite resin particle according to  claim 1  wherein the resin particle comprises a reactive group-containing prepolymer (α) and a curing agent (β). 
     
     
       17. The composite resin particle according to  claim 16  wherein the reactive group-containing prepolymer (α) contains at least one reactive group selected from the group consisting of isocyanate group, blocked isocyanate group and epoxy group and also wherein the curing agent (β) is an active hydrogen-containing compound (β1) which may be blocked with a compound which can be removed. 
     
     
       18. The composite resin particle according to  claim 17  wherein the active hydrogen-containing compound (β1) is a ketimine and/or water. 
     
     
       19. The composite resin particle according to  claim 1  obtained in such a manner that the resin (b) constituting the resin particle (B), a precursor (b0) of said resin (b) and/or a solution thereof are dispersed in an aqueous dispersion containing the resin microparticle (A) and if the precursor (b0) or a solution thereof is employed the precursor (b0) is reacted, to form the resin particle (B) comprising said resin (b) in the aqueous dispersion of the resin microparticle (A) whereby forming the resin particle as the resin particle (B) on the surface of which the resin microparticle (A) has been deposited and then the aqueous solvent is removed. 
     
     
       20. The composite resin particle according to  claim 19  obtained in such a manner that the aqueous dispersion is subjected to a high shear force upon dispersing if said resin (b) and/or the precursor (b0) is employed, and upon dispersing and if necessary upon removing the solvent if a solution of said resin (b) and/or a solution of the precursor (b0) is employed.